Neoxabea mexicana Collins & Velazco-Macias, 2021

Collins, Nancy & Velazco-Macias, Carlos Gerardo, 2021, Neoxabea mexicana sp. nov. (Gryllidae: Oecanthinae): A new species from Mexico and a key for Neoxabea in North and Central America, Journal of Orthoptera Research 30 (2), pp. 99-106 : 99-102

publication ID	https://dx.doi.org/10.3897/jor.30.62000
publication LSID	lsid:zoobank.org:pub:DAE8FB88-A170-4047-9CF2-17E53CE7EFBF
persistent identifier	https://treatment.plazi.org/id/170F61F8-6BA5-4D58-AACE-19B51DE91EE2
taxon LSID	lsid:zoobank.org:act:170F61F8-6BA5-4D58-AACE-19B51DE91EE2
treatment provided by	Journal of Orthoptera Research by Pensoft
scientific name	Neoxabea mexicana Collins & Velazco-Macias
status	sp. nov.

Treatment

Neoxabea mexicana Collins & Velazco-Macias sp. nov. Figs 1-5 View Figures 1–5 , 8-13 View Figures 8–13 , 14 View Figure 14

Type-specimen. -

Holotype ♂ (Fig. 2 View Figures 1–5 ), alcohol vial. Bosques del Rey, Guadalupe, Nuevo Leon, Mexico. 25°38.21'N, 100°12.26'W, elevation ca 580 masl, urban area adjacent to Cerro de La Silla, C.G. Velazco-Macias & J.G. Velasco-Castañon leg., 15 X 2020.

Holotype description. -

Face, head, and pronotum brown. Pedicel and scape brown, each with one protruding tubercle (Fig. 5 View Figures 1–5 ); remainder of antennomeres translucent whitish with black staining. Palpi light brownish with black line on each segment (Fig. 4 View Figures 1–5 ). Eye color brown. Wing color brown and whitish or cream. Ventral abdomen brownish with scattered staining (Fig. 9 View Figures 8–13 ). Dorsal abdomen median terga projections rounded (Fig. 10 View Figures 8–13 ). Tarsi, tibiae, and femora with translucent pale yellowish tan with no lines or spotting. Tympanal membrane on fore tibiae with whitish rim. Cerci loosely S-curved and brown (Figs 9 View Figures 8–13 , 11 View Figures 8–13 ). Total length 17.0 mm; tegminal length 12.0; tegminal width 4.0; pronotal length 3.0; distal pronotal width 2.0; hind femur length 8.0; cerci 1.5; stridulatory file length 2.0 mm. Right tegminal stridulatory teeth total 55.

Type material. -

Located October 2020 on private property in Bosques del Rey, Guadalupe, Nuevo Leon, Mexico. 2 ♂ and 1 ♀ deposited at Universidad Nacional Autónoma de Mexico (UNAM), one ♂ of these designated as the holotype for this species.

The genus Neoxabea was determined as the Nuevo Leon specimens lacked spines on the hind tibiae (Figs 1-3 View Figures 1–5 ). Males display large amounts of dark staining on the tegmina (Fig. 2 View Figures 1–5 ). Females (Figs 1 View Figures 1–5 , 3 View Figures 1–5 ) display a pair of blackish spots on the lateral edges of brown wings with areas of cream and a pair of less obvious spots embedded in the dark brown areas of the wings at the base. Both sexes have a black line on each segment of the maxillary palpi (Fig. 4 View Figures 1–5 ) and a protruding tubercle on both the pedicel and scape (Fig. 5 View Figures 1–5 ). The female in Figure 3 View Figures 1–5 actively mated with one of the two males found on the same property (video in Suppl. material 1).

Male paratype (n=1). -

Total body length 17.0 mm, tegminal length 12.5, tegminal width 5.5, pronotal length 3.5, distal pronotal width 3.0, proximal pronotal width 2.2, hind femur length 9.0, cerci 2.25. Stridulatory file length 2.0. Right tegminal stridulatory teeth total 53.

The metanotal gland, color of the ventral abdomen, cerci, distal abdominal terga projections, ovipositor, and copulatory blades are presented in Figs 8-13 View Figures 8–13 , respectively. The metanotal gland scutum to scutellum ( Walker 1967) ratio is 1:0.6. Long setae cover the ends of two curved structures situated on both sides of the scutellum that project upward into the center orifice of the gland (Fig. 8 View Figures 8–13 ). The gland area resembles that of Neoxabea femorata Walker, 1967 in figure 25 of Walker (1967); however, the scutum of N. mexicana sp. nov., is twice as wide as long and has a straight upper edge. Figure 10 View Figures 8–13 provides a closer inspection of the shapes of all eight abdominal terga projections. The most distal (eighth) projection is much smaller in size than the other seven. The cerci are robust and loosely S-shaped (Figs 9 View Figures 8–13 , 11 View Figures 8–13 , 12 View Figures 8–13 ). The copulatory blades (main lobes of pseudepiphallus) touch at the midline while in a rested position and hook upward (Fig. 13A-C View Figures 8–13 ). Photos of additional structures in Suppl. material 2.

Female (n=2). -

One female was not euthanized and only partially measured. Latticed vein pattern on wings with a single large dark pair of spots at lateral edges mid-wing (Figs 1 View Figures 1–5 , 3 View Figures 1–5 ), and a second pair of spots at the base of the wings. The degree of brown and cream varies. Total body length 16.0 mm, pronotal length 2.5-3.0, distal pronotal width 2.0-2.5, proximal pronotal width 1.5-2.0, hind femur length 7.5-8.2, cerci 2.0, ovipositor length 5.0. The tip of the ovipositor (Fig. 12 View Figures 8–13 ) does not extend beyond the tips of the hindwings.

Morphological differences. -

The maxillary palpi of N. mexicana sp. nov. have a longitudinal black line (Fig. 4 View Figures 1–5 ), which is ruddy on N. bipunctata . The numerous darkened areas on the male tegmina of N. mexicana sp. nov. are not found on N. bipunctata . Female N. mexicana sp. nov. have a pair of black spots mid wing, and a pair of spots at the base of the wings. N. bipunctata also has a total of two pairs of spots, but the proximally placed spots are not at the base of the wings. The tubercle on the pedicel of N. mexicana sp. nov. is well-developed, while there is generally a very small dimple on the pedicel of N. bipunctata . See other species comparisons in Fig. 17A-R View Figure 17 and Table 1 View Table 1 .

Song. -

Calling song recordings were made in captivity by CGV-M (Suppl. material 3, 4). Waveform review revealed that this species has bursts of trilling with 36 pulses per second at 26.6°C (Fig. 14 View Figure 14 ). Pulse rates of the songs at different temperatures by this species and three other Neoxabea species occurring in North and Central America were plotted on a pulse rate vs temperature graph (Fig. 15 View Figure 15 ). Although only a single recording with an accurate temperature for N. ottei and two recordings for N. cerrojesusensis are available, several additional recordings were analyzed, and the pulse rate never dropped below 80 pulses per second with am bient temperatures above 22°C. Permit limitations allowed only two nights of recordings. The pulses per second rate of N. mexicana sp. nov. is less than half of that for N. bipunctata , N. ottei , and N. cerrojesusensis . Spectrograms review revealed a calling song carrier frequency of 3.6 kHz at 26.6°C and 3.4 kHz for the pre-singing stuttering (Fig. 16 View Figure 16 ). When compared to the frequencies of the other three Neoxabea species mentioned above, N. mexicana sp. nov. had a more marked change in the frequency of the stuttering versus the frequency of the singing.

Calling song tone comparison. -

The tone of the trilling portion of the song of N. mexicana sp. nov. is more musical and flute-like than the buzzy sound of the faster song of N. bipunctata . Both species have a pre-trilling stuttering, but the stuttering of N. mexicana sp. nov. is longer in duration, more consistently present, and was found to be more flute-like in tone even at moderate temperature (22.7°C). Neoxabea mexicana sp. nov. has a 200 Hz difference between the frequency of the stuttering and the song trilling, while the frequency of N. bipunctata remains constant.

Key to Neoxabea species in North and Central America

1	Females	2
1'	Males (male of N. formosa unknown)	6
2(1)	Two pairs of prominent dark spots on lateral edges of female wings at rest; located in mid portion (Fig. 17C-E View Figure 17 )	3
2'	Two pairs of prominent dark spots on lateral edges of female wings at rest; with one of the pairs located at base (Fig. 17A, B View Figure 17 )	5
3(2)	Ruddy line on each segment of the maxillary palpi; slight dimple on pedicel (Fig. 17C, J, R View Figure 17 )	♀ N. bipunctata
3'	Dark brown or black line on each segment of the maxillary palpi	4
4(3')	Dimple on pedicel unknown (only scape present on holotype)	♀ N. formosa
4'	Moderate dimple on pedicel (Fig. 17D, N, Q View Figure 17 )	♀ N. ottei
5(2')	Moderate dimple on pedicel (Fig. 17B, M, P View Figure 17 )	♀ N. cerrojesusensis
5'	Prominent tubercle on pedicel (Fig. 17A, K, O View Figure 17 )	♀ N. mexicana
6(1')	Large amount of dark brown staining on male tegmina; black line on each segment of the maxilary palpi; prominent tubercle on pedicel; song with < 40 pulses per second at 26.0°C; stridulatory teeth count > 50 (Fig. 17F, K, O View Figure 17 )	♂ N. mexicana
6'	No or minimal male tegmina staining; dimple on pedicel; stridulatory teeth count < 30	7
7(6')	Ruddy line on each segment of the maxillary palpi; pedicel with slight dimple; song with > 100 pulses per second at 26.0°C (Fig. 17H, J, R View Figure 17 )	♂ N. bipunctata
7'	Dark brown or black lines on each segment of the maxillary palpi; moderate dimple on pedicel; song with >70 pulses per second at 26.0°C	8
8(7')	Tegmina dark staining pattern generally a full X; resting tegminal width > 4.5 mm (Fig. 17I, N, Q View Figure 17 )	♂ N. ottei
8'	Tegmina dark staining pattern generally the top half of an X; resting tegminal width < 4.5 mm (Fig. 17G, M, P View Figure 17 )	♂ N. cerrojesusensis

Neoxabea species comparisons .-The 13 described species of Neoxabea can be ruled out as N. mexicana sp. nov. with non-matching characters, as in Table 1 View Table 1 .